This invention pertains to the art of strain reliefs and, more particularly, to bending strain reliefs for cable or hose.
The invention is particularly applicable to protecting the central hose of an oil field blow-out preventer control umbilical at the blow-out preventer stack termination and will be described with particular reference thereto. However, it will be appreciated that the invention has broader applications and may be advantageously employed in other environments requiring limitation of flexural fatigue and kinking of a cable or hose-type structure.
Bending strain relief assemblies are commonly applied to terminal end portions or couplings of a cable, hose assembly, or the like when these structures are to be subjected to kinking during handling and operation. In an effort to alleviate the forces and stresses imposed on the hose assembly, current arrangements utilize a split hose having a dimension one size larger than the hose assembly to be protected. This difference in dimension allows the split hose to be wrapped over the kink area or area of potential flexural fatigue.
Yet another solution employs a reinforced rubber boot designed to contain an internal burst pressure. By virture of its surrounding relation at the hose assembly fitting, and due to its minimum stiffness, the boot is indirectly used to address the kinking problem with only marginal results. Since the reinforced rubber boot is not designed to specifically alleviate the flexural fatigue and kinking problems associated with the hose assembly, it has not proved wholey satisfactory.
Another problem associated with these devices is the need to position the makeshift bending strain reliefs on the hose assembly prior to termination. This adds unnecessary structure and complexity to the hose assembly during termination or coupling.
The present invention meets the foregoing needs and eliminates problems encountered with prior art structures to provide an assembly which is simple, effective, reliable, and adapted to use in a wide variety of applications and environments.